Yesterday the wireless network was playing up. The access points kept disappearing and reappearing and the driver couldn't react (note that this is on the USB ACX100).

Then, an Ad-Hoc network with the ESSID (name) "google" appeared, with a MAC address I'm quite certain doesn't exist (started with C5, I've only seen ones that start with 00. AFAIK there's no need for that yet) but then changed to the AP that sits on the town hall.

It disappeared after a while, and the network returned to normal. Strange.